Out-of-bounds read in GNU Libidn

1) Out-of-bounds read

EUVDB-ID: #VU32270

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2016-6261

CWE-ID: CWE-125 - Out-of-bounds read

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

The idna_to_ascii_4i function in lib/idna.c in libidn before 1.33 allows context-dependent attackers to cause a denial of service (out-of-bounds read and crash) via 64 bytes of input.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Libidn: 1.0 - 1.32

CPE2.3

• cpe:2.3:a:gnu:libidn:1.0:*:*:*:*:*:*:*
• cpe:2.3:a:gnu:libidn:1.1:*:*:*:*:*:*:*
• cpe:2.3:a:gnu:libidn:1.2:*:*:*:*:*:*:*

External links

https://git.savannah.gnu.org/cgit/libidn.git/commit/?id=f20ce1128fb7f4d33297eee307dddaf0f92ac72d
https://lists.opensuse.org/opensuse-updates/2016-08/msg00098.html
https://www.debian.org/security/2016/dsa-3658
https://www.openwall.com/lists/oss-security/2016/07/20/6
https://www.openwall.com/lists/oss-security/2016/07/21/4
https://www.securityfocus.com/bid/92070
https://www.ubuntu.com/usn/USN-3068-1
https://lists.gnu.org/archive/html/help-libidn/2015-07/msg00016.html
https://lists.gnu.org/archive/html/help-libidn/2016-07/msg00009.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.